The Black Hole Explorer: Operating a Hybrid Observatory

TL;DR

The Black Hole Explorer (BHEX) is a space-ground hybrid observatory designed to image black hole photon rings and measure their properties, advancing tests of general relativity and black hole physics.

Contribution

This paper presents a detailed operations plan for BHEX, integrating space and ground observations for high-resolution black hole imaging.

Findings

Proposes a coordinated observation strategy for BHEX and ground arrays.

Outlines data collection and processing workflows for the hybrid observatory.

Defines operational modes and planning processes for the mission.

Abstract

We present a baseline science operations plan for the Black Hole Explorer (BHEX), a space mission concept aiming to confirm the existence of the predicted sharp ``photon ring" resulting from strongly lensed photon trajectories around black holes, as predicted by general relativity, and to measure its size and shape to determine the black hole's spin. BHEX will co-observe with a ground-based very long baseline interferometric (VLBI) array at high-frequency radio wavelengths, providing unprecedented high resolution with the extension to space that will enable photon ring detection and studies of active galactic nuclei. Science operations require a simultaneous coordination between BHEX and a ground array of large and small radio apertures to provide opportunities for surveys and imaging of radio sources, while coordination with a growing network of optical downlink terminals provides the data rates necessary to build sensitivity on long baselines to space. Here we outline the concept of operations for the hybrid observatory, the available observing modes, the observation planning process, and data delivery to achieve the mission goals and meet mission requirements.